With the rapid growing of Internet technologies, the amount of information on the internet represents an explosive growth every day. Search engine may help a user to quickly acquire desired information among massive data by constructing an effective data index. In the technology of search engines, inverted index is a kind of data structure being widely used for storing mappings of a storage location for a term in a document or a set of documents in the context of full-text searching. Through the use of inverted index, a document list containing a keyword can be quickly acquired to generate a search result to the user.
In conventional search engines, terms for which inverted indexes are formed and document lists corresponding to the terms are generally stored in a single computing device. Because of the limited hardware resource of the single computing device, the more the terms being inverted indexed, the larger the storage space occupied by the generated inverted indexed data. Meanwhile, during the retrieving process, the frequency of read and write operations on magnetic disks will be higher. Taking 200 million pieces of documents as an example, the number of the terms being inverted indexed is more than 1.4 billion, and the amount of inverted index data corresponding to these terms is more than 560 GB. Thus, during the retrieving process, the burdens on the Central Processing Unit and the magnetic disks are too heavy to perform an efficient computation, which would impact the access speed for the inverted index data and results in a low efficiency in generating the search result.